mineral

Amethyst (Ametrine or Bicolor Quartz variant)

Silicon Dioxide (SiO2) with iron impurities

Hardness: 7 (Mohs scale), Color: Purple to violet with hints of yellow or clear, Luster: Vitreous (glassy), Crystal Structure: Trigonal/Hexagonal, Cleavage: None (Conchoidal fracture), Specific Gravity: 2.65

Identified June 19, 2026More mineral →

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Physical properties

Formation & geological history

Formed in igneous and metamorphic environments, specifically within geodes or cavities in volcanic rocks. The purple color results from gamma irradiation and iron impurities. Typical formation periods range from millions to hundreds of millions of years ago.

Uses & applications

Predominantly used as a gemstone in jewelry, for decorative carvings, and highly valued by mineral collectors for metaphysical or aesthetic purposes.

Geological facts

Amethyst was considered a precious stone comparable to diamond until large deposits were discovered in Brazil in the 19th century. The name comes from the Greek 'amethystos', meaning 'not intoxicated'.

Field identification & locations

Identify in the field by its distinct purple color and crystal habit. It can be found globally with major deposits in Brazil and Uruguay. Smaller crystals can be found in stream beds or within volcanic outcroppings.

Other mineral specimens

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Sandstone (with potential mineral staining/concretions)

Arenite (SiO2 based)

sedimentary

Schist

Metamorphic

Epidote

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metamorphic

Nephrite Jade

Nephrite

Mineral/Rock

Banded Gneiss (River Rock/Pebble)

Gneiss (specifically a banded variety often found as a river rock)

Metamorphic Rock

Green Apatite on Albite

Fluorapatite [Ca5(PO4)3F] on Albite [Na(AlSi3O8)]

mineral